Interpretive Summary: This publication discusses the limitations of the original data in the study by Zhang and Montgomery on the use of digital landscapes for hydrologic applications. It further shows that the conclusions reached by Zhang and Montgomery may be in part the result of the limitations of the data. General guidelines for the proper selection of digital landscapes for hydrologic applications are proposed.

Technical Abstract:
This paper review the study by Zang and Montgomery on the effect of Digital Elevation Model (DEM) grid size on landscape characterization and hydrologic simulation of catchment response. The limitations of the study are clarified by drawing attention to the resolution of the original topographic data from which their DEMs of various grid size were generated. .We believe that the conclusions of the study are in part due to the limitations of the data, and not necessarily attributable to changes in DEM grid size as stated. We suggest that general guidelines for DEM grid size for hydrologic applications should consider landscape characteristics, hydrologic model type and model parameters.